Hi Everyone,
I have a set of impellers which are 17-4PH base material, they have had the wear ring diameters laser clad with Stellite 6, these impellers operate in 160 DegC water. My query is this - is the stellite 6 likely to crack (or can it de-laminate) due to the different materials thermal growth?

I am not the expert, but what i am seeing is, if the coating is dense enough, the stress can cause it to crack. Since 17-4 is a
stainless steel material, it does expends with heat. My suggestion is to have a test sample

(03-10-2011 02:52 PM)djewell Wrote: The CTE's of Stellite 6 and 17-4 are very close (~12 um/m-K and ~11 um/m-K respectively). I think it is very unlikely that the coating will crack at such a low temperature.

Thanks very much for your replies guys, I have tested one of the impellers - I preheated an oven to 300 DegC and placed the impeller in there for 1 hour, removed it and let it cool quickly outside in ambient temperature, so basically I have treated it far more extreme than it would see in service.
I cracked checked prior and post heat and found no cracks, the test was repeated and still no cracks.

So I am now of the opinion that it is safe to use the components with the stellite 6 applied.

I am a student
I do research about tig cladding on 17-4ph.
In your opinion, what is the best filler to cladding?Except stellite 6
Is good (Tribaloy 900, stellite 1, Deloro 60) for abrasion resistance and corrosion?
Do thye have good weldability with 17-4ph?
why you do not cladding whit (Tribaloy 900, stellite 1, Deloro 60) ?
thye have hardness above stellite 6.